Shortened relative leukocyte telomere length is associated with prevalent and incident cardiovascular complications in type 2 diabetes : analysis from the Hong Kong Diabetes register

OBJECTIVE: Several studies support potential links between relative leukocyte telomere length (rLTL), a biomarker of biological aging, and type 2 diabetes. This study investigates relationships between rLTL and incident cardiovascular disease (CVD) in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Consecutive Chinese patients with type 2 diabetes (N = 5,349) from the Hong Kong Diabetes Register for whom DNA obtained at baseline was stored and follow-up data were available were studied. rLTL was measured by using quantitative PCR. CVD was diagnosed on the basis of ICD-9 code. RESULTS: Mean follow-up was 13.4 years (SD 5.5 years). rLTL was correlated inversely with age, diabetes duration, blood pressure, HbA1c, and urine albumin-to-creatinine ratio (ACR), and positively with estimated glomerular filtration rate (eGFR) (all P < 0.001). Subjects with CVD at baseline had a shorter rLTL (4.3 ± 1.2 ΔΔCt) than did subjects without CVD (4.6 ± 1.2 ΔΔCt) (P < 0.001). Of the 4,541 CVD-free subjects at baseline, the 1,140 who developed CVD during follow-up had a shorter rLTL (4.3 ± 1.2 ΔΔCt) than those who remained CVD-free after adjusting for age, sex, smoking, and albuminuria status (4.7 ± 1.2 ΔΔCt) (P < 0.001). In Cox regression models, shorter rLTL was associated with higher risk of incident CVD ( for each unit decrease, hazard ratio 1.252 [95% CI 1.195–1.311], , P < 0.001), which remained significant after adjusting for age, sex, BMI, systolic blood pressure, LDL cholesterol, HbA1c, eGFR, and ACR (hazard ratio 1.141 [95% CI 1.084–1.200], P < 0.001). CONCLUSIONS: rLTL is significantly shorter in patients with type 2 diabetes and CVD, is associated with cardiometabolic risk factors, and is independently associated with incident CVD. Telomere length may be a useful biomarker for CVD risk in patients with type 2 diabetes.